Light-sensitive silver halide direct-positive photographic emulsion

ABSTRACT

THE EMULSION CONTAINS A SENSITIZING DYE, AT LEAST ONE COUPLER SELECTED FROM THE GROUP CONSISTING OF MAGENTA, YELLOW AND CYAN COUPLERS, AND A RHODIUM COMPOUND. FOGGING IS INHIBITED SENSITIVITY TO LIGHT OF LONG WAVELENGTH IS INCREASED AND REVERSAL SPEED IS INCREASED. ADDITIONALLY WHITE BACKGROUND DYE STAINING IS SUPPRESSED.

'April 27,1971 zuo MATSUI ETAL 5 3,576,636

LIGHT-SENSITIVE SILVER HALIDE DIRECT-POSITIVE PHOTOGRAPHIC EMULSION 7 Filed D80. 16, 1968 2 ShGGtS-ShGQt l Fig! v I I l Wavelength (mm Fig. 2 v ,f/

I l I 550 500 550 500 450 1.00 350 Wavelengthmp) Fig. 3

-Wavelength(1np) Fig.5

5'50 500 550 500 1.50 4'00 350 --Wavelength(mp) INVENTORS KAZUO MA'rsui HAJIME KOMATSU ATTORNEYS KAZUO MATSUI ET AL 3,576,636

April 27, 1971 LIGHT-SENSITIVE SILVER HALIDE DIRECT-POSITIVE PHOTOGRAPHIC EMULSION 2 Sheets-Sheet 2 Filed Dec. 16, 1968 Fig.6

I {I /\\-/Y, w 550 500 550 500 1.50 400 350- ---Wavelength (any Wavelengthump) Fig.8

4 00 vhvelengthmnf INVENTORS KAZUO MATSUI HAJIME KOMATSU ATTORNEYS United States Patent Int. Cl. odsc 1/40 US. Cl. 96-100 Claims ABSTRACT OF THE DISCLOSURE The emulsion contains a sensitizing dye, at least one coupler selected from the group consisting of magenta,

yellow and cyan couplers, and a rhodium compound. Fogging is inhibited, sensitivity to light of long wavelength is increased and reversal speed is increased. Additionally, white background dye staining is suppressed.

This invention relates to light-sensitive silver halide direct-positive photographic emulsion which can directly give positive images by single exposure and single development.

An object of the present invention is to provide supersensitized light-sensitive silver halide direct-positive photographic emulsion which has been optically sensitized with sensitizing dyes having sensivity to light of specific wavelength.

Heretofore, there have been known light-sensitive silver halide direct-positive photographic emulsions optically sensitized by incorporation of a cyanine dye as a sensitizing dye or supersensitized by incorporation of a cyanine dye in combniation with an organic desensitizer.

However, the said known photographic emulsions had suck drawbacks that they contained a sensitizing dye at so high concentration that the sensitizing dye stained the white background of photographic materials after development. Further, in the case of the photographic emulsions incorporated with a cyanine dye in combination with an organic desensitizer, there have been observed such drawbacks that the emulsions incorporated with monomethine cyanine dyes were supersensitized, whereas those incorporated with trimethine cyanine dyes were hardly supersensitized. In addition, when rhodium compounds were used as desensitizers in combination with cyanine dyes, the resulting photographic emulsions were increased in fog and were diificultly put into practical use.

Accordingly, in the known light-sensitive silver halide direct-positive photographic emulsions, use of sensitizing dyes providing excellent photographic characteristics, i.e. merocyanine dyes, trimethine-cyanine dyes and the like, was greatly limited. Therefore, it was very difficult to prepare light-sensitive silver halide direct-positive photographic emulsions having light sensitivity to light of long wavelength and less sulfering from fogging.

After the investigations, it has been found that lightsensitive silver halide direct-positive photographic emulsions improved in fogging and other photographic prop erties and supersensitized only in the specific wavelength portions, can be obtained by incorporating into lightsensitive silver halide direct-positive photographic emulsions containing a rhodium compound and a sensitizing dye which is sensitive to light of long wavelength such as merocyanine dye or trimethine cyanine dye one or more of magenta, yellow and cyan couplers.

The magenta couples used in this invention are those i'epresente'd by any one of the followinggeneral formu- R2 N=C-(NHCO)n-R1 R3 I F- H;

a m /N=C(NHGO)n-R N X: C- H l N Xi (H) crvomco-Q NHCO-Rr (III) in which R, is a higher alkyl, alkoxyaryl or acrylaminoaryl group, whose alkyl portion may have a carboxyl or sulfonic acid group as a substituent;

R is hydrogen, halogen, carboxyl group or sulfonic acid R is hydrogen or halogen;

R is hydrogen, halogen or phenoxy or alkylphenoxy group, whose phenyl group may have an alkyl group as a substituent;

X and X are each hydrogen, sulfonic acid group or its alkali metal salt group; and n is 0 or 1.

The yellow couplers used in this invention are those having the following fundamental structure:

Both phenyl groups may have an appropriate substituent. The cyan couplers used in this invention are those represented by the following general formula:

CONH(GH2)nR Magenta couplers 51 OH 4 S i I v y H v CONHCHzGHr-Q-NHCOCHHas H =T S O=C-N CH3 02H SOsH (a) s v 52 OH H o =CH-CH=C--S monnomom-Qrmcocmen-omms H; N L is COOH 0:

' I CH QH=OH 53 OH 6 4 CH-CH=CS CONH(CH2)3NHGOCHzCHC1aHa1 0 =3 COOH (54) OH CHal-N-CmHav (7) g I HaCO CHCH=CS o0NHoHzoH2co1-iH 0 J lzHs I CH3 soiH i (s) s s r (65) OH CHs-N-CxsHsv l (JR-0:011-

CONHHC CONH- f 9 s s 0311 U err-0:011-

Rhodlum compounds employed in the present invention are soluble salts or complex salts of rhodium. Par- 7 N N tifiullaily preferable are rhodium halides and hexahalo- (831120450313 3 3 9 r o a es.

dyes are used and typical compounds of such dyes are As the sensitizing dyes having sensitivity to light of .5 S long wavelength, merocyanine dyes, trimethine cyanine 0:011 exemplified below.

| I has $11920cmorromsoa cm-Q-sm 1 l fogging. Typical organic desensitizers' are, for example, pinakryptol yellow, pinakryptol green and phenosafranine. The organic desensitizer is preferably added in an amount of about 100 mg.-l.5 g. per mole of silver halide. The magenta coupler, yellow coupler and cyan coupler may be used in combination.

The rhodium compound is usually added at the stage of emulsification of silver halide or physical ripening in an amount of about 1 X 10* to 1 10- mols per mol of silver halide. The sensitizing dye having sensitivity to light of long wavelength is added in an amount of 1 -800 mg. per mole of silver halide. The sensitizing dye may be added singly or in admixture with two or more of them.

The emulsion employed in the present invention may be a silver chloride-, silver bromide-, silver iodide-, silver chlorobromide-, silver chloroiodide-, silver bromoiodideor silver chlorobromoiodide-emulsion containing gelatine or other hydrophilic organic colloid as a protective colloid. Particularly preferable emulsion is a silver chlorobromoiodide emulsion prepared according to the neutral or acidic method and containing a small amount of silver iodide. Such emulsion has appropriately been fogged by chemical treatment in the preparation thereof. The emulsion may be incorporated with various aids such as stabilizer, hardening agent and matting agent which are ordinarily used in common light-sensitive silver halide photographic emulsions.

As is clear from the above, the conventional lightsensitive silver halide direct-positive photographic emulsions containing rhodium compound and optically sensitized with sensitizing dyes have such drawback that they are increased in fog and are injured in photographic properties. In case an organic desensitizer is added in order to inhibit fogging, the object of inhibiting fogging can be attained but there is brought about such drawback that optical sensitization with a sensitizing dye difiicultly takes place due to the organic desensitizer.

The light-sensitive silver halide direct-positive photographic emulsions of the present invention have no such drawbacks. In the emulsions, increase of fogging is inhibited and optical sensitivity is improved. Moreover, in accordance with the present invention, sensitizing dyes having sensitivity to light of optional long wavelength can be selected from a broader scope. Further, the amount of sensitizing dye, which is required to attain the same sensitivity as that of the conventional light-sensitive silver halide direct-positive photographic emulsion, can be made smaller and dye staining on the white background of lightsensitive material after development can be prevented.

The present invention is illustrated in detail below with reference to examples.

EXAMPLE 1 A rhodium compound (rhodium chloride)-containing silver chlorobromiodide emulsion which comprises 3 mole percent of silver iodide and 20 mole percent of silver bromide was adjusted to pH 8.0 with an alkali. Subsequently, the emulsion was charged with 5 cc. of 3% Formalin per kg. of said emulsion and then subjected to the ripening at 50 C. for 20 minutes. After the ripening, pH was adjusted to 6.0 with an acid.

The thus treated emulsion was divided into 2 portions. One portion was added with cc. of 0.05% methanol solution of the sensitizing dye (17), 200 cc. of 0.1% aqueous solution of pinakryptol yellow and 30 cc. of 10% aqueous solution of saponin to prepare a sample (A). To the other portion of said emulsion, in addition to the above-mentioned additives, a solution of 7 g. of the coupler (2) in an alkali which solution had been adjusted to pH 6.0 was added to prepare a sample (B). The samples (A) and (B) were individually coated onto a photographic baryta paper and dried.

The thus obtained light-sensitive materials were individually subjected to stepwise exposure through a yellow filter transmitting a light of wavelength longer than 450 m and treated with the D-72 developer (dope: water=1:1). The results obtained are as shown in Table 1, wherein sensitivity is expressed as relative value to the speed of the sample (A) ratet as 100.

TABLE 1 Relative speed Fog Sample EXAMPLE 2 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion treated in the same manner as in Example 1, the following samples (A) and (B) were prepared:

(A) The emulsion added with 10 cc. of 0.05% methanol solution of the light-sensitive dye (17 200 cc. of 0.1% aqueous solution of pinakryptol yellow and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with an alkali solution of 8 g. of the coupler (4.) which had been adjusted to pH 6.0 besides the additives used in the sample (A).

The samples (A) and (B) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 2, wherein sensitivity is expressed as relative value to the speed of the sample (A) rated as 100.

TABLE 2 Relative speed Fog Sample EXAMPLE 3 A rhodium compound-containing silver chlorobromide emulsion which comprises 30 mole percent of silver bromide was chemically fogged in the same manner as in Example 1. Using each 1 kg. of the thus obtained silver chlorobromide emulsion, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 12.5 cc. of 0.05% methanol solution of the sensitizing dye (17) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with a solution of 8 g. of the coupler ('12) which had been adjusted to pH 6.0, besides additives used in the sample (A).

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(B) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 3, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

Relative speed The spectral sensitivity curves of said samples are shown in FIG. 2, in which the sample (A) as referred sample (B) to sample (C) and sample (D) to The samples containing the couplers according to the present invention were remarkably supersensitized and increase of fogging was very slight as compared with the samples containing no such couplers.

EXAMPLE 4 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 12.5 cc. of 0.05% methanol solution of the sensitizing dye (17) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of "8 g. of the coupler (16) in which had been adjusted to pH 6.0.

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The, emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 4, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 4 EXAMPLE 5 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A) and (B) were prepared: 7

(A) The emulsion added with 10 cc. of 0.05 methanol Table 6.

TABLE 6 Relative speed Fog Sample The spectral sensitivity curves of said samples are shown in FIG. 3, in which the curve of sample (A) is 14 represented by the chain line and that of sample (B) by the solid line.

EXAMPLE 6 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 15 cc. of 0.05 methanol solution of the sensitizing dye (18) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 8 g. of the coupler (12) which had been adjusted to pH 6.0.

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 7, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 7 oowee ammo EXAMPLE 7 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 15 cc. of 0.05 methanol solution of the sensitizing dye (20) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 8 g. of the coupler (20) which had been adjusted to pH 6.0.

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 8, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 8 Relative speed The spectral sensitivity curves of said samples are shown in FIG. 5, in which the sample (A) is referred to sample (B) t sample (C) to and sample (D) to EXAMPLE 8 Using each 1 kg. of a forged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

'(A) The emulsion added with cc. of 0.05% methanol solution of the sensitizing dye (4), 8 cc. of 0.05 methan l solution of the light-sensitive dye (17) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives use in the sample (A) and an alkali solution of 10 g. of the coupler (12) which had been adjusted to pH 6.0.

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 9, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 9 Relative speed The spectral sensitivity curves of said samples are shown in FIG. 6, in which the sample (A) is referred to sample (B) to sample C) to and sample (D) to From the above, it is understood that even when two kinds of sensitizing dyes were used together, supersensitization took place.

Likewise, favorable results were obtained even when three kinds or more light-sensitive dyes were used together.

EXAMPLE 9 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A) and (B) were prepared:

(A) The emulsion added with 12 cc., of 0.05% methanol solution of the light-sensitive dye (17), 200 cc. of 0.1% aqueous solution of pinakryptol yellow and .30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 3 g. of the coupler (4) and 7 g. of the coupler (41) which solution had been adjusted to pH 6.0.

The samples (A) and (B) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 10, wherein sensitivity is expressed as relative value to the speed of the sample (A) rated as 100.

As seen in the Table 10, the sample (B) containing the coupler according to the present invention was not only greatly sensitized but also free from increased fogging.

16 EXAMPLE 10 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedures as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 12 cc. of 0.05 methanol solution of the sensitizing dye (17 and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 5 g. of the coupler (41) and 5 g. of the coupler (46) which had been adjusted to pH 6.0.

(C) The emulsion added with the additives use in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 11, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 11 Relative speed Fog EXAMPLE 11 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion prepared according to the same procedure as in Example 1, the following samples (A) and (B) were prepared:

(A) The emulsion added with 12.5 cc. of 0.05 methanol solution of the sensitizing dye (17 200 cc. of 0.1% aqueous solution of pinakryptol yellow and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 8 g. of the coupler (46) which had been adjusted to pH 6.0.

The samples (A) and (B) were independently coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 12, wherein sensitivity is expressed as relative value to the speed of the sample (A) rated as 100.

The spectral sensitivity curves of said samples are shown in FIG. 8, in which the solid lines exhibit the curves obtained by the sample (B) and the dotted lines exhibit the curves obtained by the sample (A).

The sample (B) which is a light-sensitive emulsion ac-- cording to the present invention was not only supersensitized but also free from increase in fogging;

17 EXAMPLE 12 Using each 1 kg. of a fogged silver chlorobromoiodide emulsion obtained according to the same procedure as in Example 1, the following samples (A), (B), (C) and (D) were prepared:

(A) The emulsion added with 15 cc. of 0.05% methanol solution of the sensitizing dye (17) and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 8 g. of the coupler (46) which had been adjusted to pH 6.0.

(C) The emulsion added with the additives used in the sample (A) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

(D) The emulsion added with the additives used in the sample (B) and 200 cc. of 0.1% aqueous solution of pinakryptol yellow.

The samples (A), (B), (C) and (D) were individually coated onto a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 13, wherein sensitivity is expressed as relative value to the speed of the sample (C) rated as 100.

TABLE 13 The spectral sensitivity curves of said samples are shown in FIG. 9, in which the sample (A) is referred to sample (B) to sample (C) to and sample (D) to EXAMPLE 13 Example 121 was repeated using a silver chlorobromide emulsion in place of the silver chlorobromoiodide emulsion. The emulsion according to the present invention gave good results.

EXAMPLE 14 TABLE 14 oowco man c Use of the sensitizing dyes (23) and (26) gave good results.

EXAMPLE Example 121 was repeated using the coupler (50) in place of the cyan coupler (46) used therein. The results obtained are as shown in Table 15, wherein the samples (A"), (B"), (C) and (D) correspond to the samples (A), (B), (C) and D) used in Example 121, respectively.

TABLE 15 Relative speed 18 EXAMPLE 16 Using each 1 kg. of a similar emulsion as used in Example 12, the following samples (A) and (B) were prepared:

(A) The emulsion added with 15 cc. of 0.05% methanol solution of the sensitizing dye (30), 200 cc. of 0.1% aqueous solution of pinakryptol yellow and 30 cc. of 10% aqueous solution of saponin.

(B) The emulsion added with the additives used in the sample (A) and an alkali solution of 8 g. of the coupler (52) which had been adjusted to pH 6.0.

The samples (A) and (B) were individually coated on a photographic baryta paper and dried. The resulting photographic materials were treated in the same manner as in Example 1. The results obtained are as shown in Table 16.

TABLE 16 Relative speed Fog Sample in which R is a higher alkyl, alkoxyaryl or acylaminoaryl group, whose alkyl portion may have a carboxyl or sulfonic acid group as a substituent;

R is hydrogen, halogen, carboxyl group or sulfonic acid R is hydrogen or halogen;

R is hydrogen, halogen or phenoxy or alkylphenoxy group, whose phenyl group may have an alkyl group as a substituent;

X and X are each hydrogen, sulfonic acid group or its alkali metal salt group; and n is 0 or 1.

3. An emulsion as claimed in claim 1, in which as the yellow coupler a compound having the following fundamental structure is used:

in which both phenyl group may have an appropriate substituent.

4. An emulsion as claimed in claim 1 in which as the cyan coupler a compound of the following general formula is used:

' 19. 20 in which R is a higher alkyl, acyl, acylamino, acylamino- 2,566,263 8/1951 'Trivelli et al 9666.4 aryl, alkylaminoaryl or alkoxyor aryloxy-aryl group, in 2,566,245 8/ 1951 Trivelli et a1. 96110 which the alkyl portion, the aryl portion, or the alkyl por- 3,352,672 11/1967 Hoppe 96100 tion and aryl portion are substituted by a carboxyl or sul- 3,367,778 2/ 1968 Berriman 96101 fonic acid group, X is hydrogen or a sulfonic acid group 3,416,927 12/1968 Kalenda 96- -102X andnis0,1,2or3. 5

5. An emulsion as claimed in claim 1, in which an or- WILLIAM D. MARTIN, Primary Examiner ganic desensitizer is used in combination with a coupler. PIANALTO Assistant Examiner References Cited 10 Us. CL XR.

UNITED STATES PATENTS 102, 109 2,448,060 8/ 1948 Smith et a1 96108 I 

